1. Technical Field of the Invention
The present invention relates to an electronic control apparatus for vehicles which updates, upon being transferred from one vehicle to another, vehicle identification information stored in the apparatus.
2. Description of the Related Art
Conventionally, for example as disclosed in Japanese Patent First Publication No. 2001-301572, an engine ECU (Electronic Control Unit) for a motor vehicle has a VIN (Vehicle Identification Number) stored in a memory (e.g., an EEPROM) thereof; the VIN is unique to the vehicle.
Moreover, in addition to the VIN, the engine ECU also has stored in the memory thereof immobilizer identification information, various types of diagnostic information, and learning values for control of the vehicle. Here, the immobilizer identification information denotes information which is unique to the vehicle or a valid user (or users) of the vehicle and is used to identify whether a user intending to activate the vehicle is the valid user.
More specifically, upon detection of immobilizer identification information from a portable device (e.g., an ignition key) of the user intending to activate the vehicle, the engine ECU or an immobilizer ECU of the vehicle crosschecks the detected immobilizer identification information against the immobilizer identification information stored in the memory. When the detected identification information coincides or matches with the immobilizer identification information stored in the memory, the engine ECU or the immobilize ECU identifies the user intending to activate the vehicle as the valid user and allows the identified user to activate the engine of the vehicle.
Furthermore, when the engine ECU is removed from the vehicle and installed to a new vehicle, it is necessary to update the VIN stored in the memory with the VIN of the new vehicle. This is because without updating the VIN stored in the memory of the engine ECU, the new vehicle cannot pass the motor vehicle inspection conducted by the government.
In addition, future OBD-related regulations will probably stipulate that all emission-related diagnostic information stored in the engine ECU be erased when updating the VIN stored in the memory of the engine ECU. Here, OBD stands for On-Board Diagnostics.
Moreover, it is preferable that other information stored in the engine ECU than the VIN and emission-related information be updated along with the VIN. It is further preferable to minimize the man-hours needed to update the information other than the VIN and emission-related information.